The winding of yarns is performed on yarn winding machines, which are described for example in U.S. Pat. Nos. 3,861,607 or 4,216,920. The winding machines have at least two spindles for holding bobbins, the spindles being rotatably mounted on a turret disc. The yarn is wound on one bobbin to form a yarn package. Once the package is full, doffing occurs, which means that the turret disc rotates and the yarn is led to the second bobbin and simultaneously cut and wound on the second bobbin.
At this point, it may occur that the loose end of the yarn of the rotating package of the first bobbin entangles in other parts of the yarn winding machine like the rotating second bobbin, leaving pieces of yarn in the second bobbin and in the winding machine, where it may contribute to off-quality yarn packages.
These packages may create problems for the end use during the manufacture of, for example, textiles or carpets, because of breakages of the yarns during unwinding from the packages.
There are proposals to reduce the yarn entanglement by, for example, special axially slidable thread gripping means as described in U.S. Pat. No. 4,460,133.
U.S. Pat. No. 4,230,285 discloses a traversing device for a thread winding apparatus which has a traverse slot, from where an air stream is directed outwardly to prevent the thread being wound or broken filaments thereof from entering the housing of the traversing device and being wrapped around the cam roller or interfering with the traversing thread guide in the housing.
Research Disclosure, January 1981, anonymous Disclosure No. 20140, "Control of Loose Yarn Ends at Package Doff," describes a yarn winding machine with a jet which is located close to the drive roll in order to provide a sheet of air along the length of the drive roll. The velocity of the jet is selected to exceed the velocity of the current of air rotating with the drive roll. One disadvantage of this fixedly mounted jet is that the produced sheet of air does not cover both ends of the two yarn packages equally well.
An object of the present invention is, to provide a device for a yarn winding apparatus which reduces the entanglement of loose yarn ends of a fully wound yarn package with a new winding yarn package and with other parts of the winding apparatus and reduces the amount of waste yarn ends in the winding apparatus.